Journal of
Science and Technology-The University of Danang, JST-UD, is an
independent peer-reviewed journal, applying international standards, inheriting
the achievements of 40 years of scientific and technological information
activities of Da Nang University and member institutions.
JST-UD operates under License No. 510/GP-BVHTT, dated November 25, 2002
by the Ministry of Culture and Information and international standard code ISSN
1859-1531 (according to Official Letter No. 44/TTKHCN-ISSN, February 6, 2007 of
the National Center for Scientific and Technological Information under the
Ministry of Science and Technology). It is a scientific journal with a high
number of access and reference.
JST-UD publishes quality scientific works in Vietnamese, English or
French (License No. 210/CBC, 5 March 2008 of the Press Department, Ministry of
Information and Communication) and Published yearly 15 numbers, including 3 in
English (License No. 07 / GP-BTTTT, January 7, 2016 by the Ministry of
Information and Communication).
The Journal
"Science and Technology" of the University of Danang is for purposes:
- Publishing new and multi-disciplinary
scientific and technological research works;
- Reviewing information on advances in
science and technology for the teaching, research and study of lecturers and
students;
- Propagating the guidelines and policies
of the Party and the State in the fields of education, training as well as in
scientific and technological researches.
JST-UD is pleased to receive many-sided cooperations of scientists,
educators, researchers in and outside the University of Danang as well as
national and international researchers to improve the prestige and the quality
of the Journal.
CURRENT ISSUE | Vol. 17, No. 10.1, 2019
Author: , Nguyễn Đình Lâm
Code: JST-UD2019-100 | Page: 1-4 of Vol. 17, No. 10.1, 2019 |
AbstractThis paper reported investigation results of the effect of the difference structures of 1D and 2D nanocarbon materials on thermal performances of Epoxy coatings. Nanocarbon material oxidative methods were proceed to improve compatibility and dispersability in Epoxy resin in this study. This may affect on the thermal properties of the coating. In there the thermal gravimetric analysis (TGA) and thermal conductivity coefficient measurement methods were employed to test the thermal properties of Epoxy paint coatings. The results showed that addition the 1D of carbon nanotubes (CNTs) and 2D of Graphene structure hybrid of nanocarbon in Epoxy films increased thermal performances of Epoxy coatings significantly. In there the effect of 1D and 2D structure hybrid of oxidative nanocarbon of oxidized CNTs (O-CNTs) and Graphene oxide(GO) that growed degree of them was higher 100% than the one of neat nanocarbon (CNTs and Graphene) and single structure of them.
Author:
Code: JST-UD2019-141 | Page: 5-8 of Vol. 17, No. 10.1, 2019 |
AbstractThis paper reports the use of glutaraldehyde for crosslinking poly(vinyl alcohol) (PVA), a biodegradable synthetic polymer, to improve its water resistance and mechanical strength to expand its application. Factors affecting the curing process including glutaraldehyde (GA) content, catalyst content, temperature and curing time have been investigated. The results show that the best curing conditions are: the weight ratio of GA to PVA: 1/100; the weight ratio of catalyst to PVA: 3.5/100, curing temperature of 90oC and curing time of 7 hours. PVA film after curing has less water sorption; the water vapor transmission through the film also decreases, tensile strength, heat resistance are improved.
Author: , Hồ Đăng Phú, Trần Thanh Tin
Code: JST-UD2019-076 | Page: 9-12 of Vol. 17, No. 10.1, 2019 |
AbstractAutomatic multi-channel system is used to measure shrinkage of concrete using electronic sensors of vibrating wire type with high accuracy and stability when measuring in a long time. It is easy to dismount, move, reuse many times. Multi-channel data acquisition device can expand the number of measuring channels to meet the research with a large number of samples. This system can also automatically and quickly collect data and reduce the measurement pressure for related studies. The interface shows the experimental process on the map and the data sheet helps users easily track the results of the experiment. Users can choose to compare the measurement data among the samples to get an overview of the experiment as well as store experimental data via text or Excell spreadsheet to facilitate the data entry process, remove errors due to data entry.
Author: Nguyễn Hữu Thọ,
Code: JST-UD2019-114 | Page: 13-17 of Vol. 17, No. 10.1, 2019 |
AbstractThis paper presents a Low-dropout regurator (LDO) with wide range input voltage on 180 nm TSMC CMOS process. The LDO circuits in the literature with wide range input voltage use complex circuit architecture, cascode some LDOs with so much power dissipation and area. For this reason, this paper proposes a simple LDO including an added block at input to extend operation range. In addition, to further improve LDO performances, buffer impedance attenuation technique is realized to build an intermediate stage for driving the PMOS pass device. The simulation shows the LDO circuit obtains 3.6 V to 12.6V of input voltage and a low dropout voltage of 300 mV.
Author: , Lê Công Tín
Code: JST-UD2019-130 | Page: 18-23 of Vol. 17, No. 10.1, 2019 |
AbstractThis paper presents the procedure of designing CAE applications to optimization and structural durability analysis in the normal load cases of buses to implement the new design of Thaco City B60 bus body. HyperWorks software has been used to simulate body construction durability and displacement, with inertial compensation, 8 load modes when carrying a rated number of 60 people. The body structure is optimized from the point of view of volume reduction, with the conditions of the materials used and the current technology of THACO. Simulation tools help shorten the design process, optimize the process of designing and manufacturing the product. Simulation results help reduce testing costs and reduce potential product defects; confirm the reliability of the product; contributing to reducing product costs and improving the environment.
Author: , , Phan Thị Hoài
Code: JST-UD2019-104 | Page: 24-29 of Vol. 17, No. 10.1, 2019 |
AbstractWalker’s movement estimation is very important in walking parameter estimation and health evaluation for walker users. This paper proposes a method to apply an Inertial Navigation Algorithm (INA) to the movement estimation of a two front-wheel walker to estimate the walker’s trajector. An IMU is fixed with the frame of walker and two encoders are used to measure the rotation of walker’s wheels. The IMU’s data is used in the model of the Kalman fillter used in the INA. The encoders’ data is used as a measured value to derive measurement equations of the Kalman fillter. We have conducted an experiment to evaluate the accuary of the proposed algorithm. The result of the experiment shows that the proposed algorithm is good and gets high accuracy (> 98%).
Author:
Code: JST-UD2019-119 | Page: 30-34 of Vol. 17, No. 10.1, 2019 |
AbstractThis study uses routine scientific research methods to assess the situation and factors affecting students' practice of Shuttlecock. On that basis, the study proposes measures to improve the efficiency of the practice of Shuttlecock for non-major students of College of Education,Thai Nguyen University including: Increasing investment in facilities and training facilities; strengthening education and propaganda to raise awareness and understanding of the content, methods and meanings of sports training; actively organizing extracurricular activities with the form of collective training with instruction and management of teachers; reducing the number of students who are staffed in one class (15 – 20 students/class). These measures are important for increasing efficiency of shuttlecock practice for non major students, thereby improving the results of physical training education and speeding up the sports movement at the university.
Author:
Code: JST-UD2019-024 | Page: 35-42 of Vol. 17, No. 10.1, 2019 |
AbstractThe paper analyzes the impacts of the contract farming (CF) on income of farmer households (FH) in the Ho Chi Minh City. The sustainable livelihood approach is used to understand the income through understanding the livelihood capitals and livelihood strategies. Qualitative research methods throughout, combined with quantitative research. Using data through the sampling survey in 2017, 2018 with 532 FH and by two-step regression method. In the first step, the Probit model used to analyze the impact of factors on the opportunity to implement the CF; in the second step, the OLS model to verify the influence of CF on the income of the FH. The results show that investment capital, income, land and prices increase the possibility of cooperation. On the contrary, cumbersome procedures, advanced age and better income from non-agricultural activities will prevent the FH participating in the CF. At the same time, the results also show that CF increases the income of the FH. The study has implications towards improving opportunities for implementing CF of the FH.
Author:
Code: JST-UD2019-086 | Page: 43-47 of Vol. 17, No. 10.1, 2019 |
AbstractThe idea of Vietnam’s opening, cooperating and integrating into the world has been sprung up in the very early days of the modern Vietnamese diplomacy under the leadership of President Ho Chi Minh. In the Doi Moi era, with creative application of Ho Chi Minh’s Thoughts on international cooperation and integration, the Communist Party of Vietnam has gradually supplemented, improved and developed its perception on international integration in accordance with the evaluation of the world situation, international relations, new trends, the interactive relations between Vietnam and the world, opportunities and challenges for Vietnam in realizing the goals of security, development and raising its position in the international arena. The research paper will focus on studying the evolution of the Communist Party of Vietnam’s perception on international integration, a crucial factor contributing to significant achievements in the cause of national renovation in general and foreign policy renewal in particular.
Author: , Võ Ngọc Hiển
Code: JST-UD2019-101 | Page: 48-53 of Vol. 17, No. 10.1, 2019 |
AbstractPhong Phu district, An Giang province in the first half of the 19th century was one of the new lands to be explored; although the land area was relatively large, the area of cultivation was not much. Ownership of private land here was different in terms of proportions, private field land occupied majority, but the scale of private ownership was small and fragmented, not reaching the maximum concentration like other areas in Cochinchina. The difference of ownership of private land was influenced by characteristic factors of the history of reclamation, natural conditions and the political-socio situation of Phong Phu district. In another perspective, studying land management in Phong Phu district in the first half of the 19th century will give historical lessons of practical value for the policy of managing and using the current land fund in Can Tho city.